• 토지주택연구
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• 제12권1호
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• pp.129-137
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• 2021

외부 차양장치는 대표적인 여름철 일사조절 장치이다. 특히 냉방부하가 높은 업무용 건물에 적합한 기술로 인식되어왔다. 그러나 본 연구에서는 차양장치의 냉방부하 저감뿐만 아니라 난방부하 저감 효과를 검증하기 위한 실험을 수행하였다. 이를 위해 겨울철 야간 천공복사냉각에 따른 영향을 중심으로 일반 창호, 롤 블라인드, 외부 차양장치를 대상으로 실험을 수행하였으며, 그 결과는 다음과 같다. 외부 차양장치가 적용된 경우 유리 내·외표면 온도차는 평균 11.8℃로 차양장치가 없는 경우의 14.6℃ 보다 평균 2.8℃ 낮은 온도차를 나타냈으며, 이는 천공복사에 의한 열교환으로 차양 표면온도가 외기온도보다 낮은 시간때에 발생한다. 한편, 롤 블라인드는 내부 중공층의 평균온도보다 0.8℃ 낮은 온도를 나타냈으며 이 또한 투과체를 통과한 천공복사가 롤 블라인드 표면과 열교환이 이뤄졌기 때문이다. 유리 외부 표면온도만을 고려하면 약 3℃ 이상의 온도 상승이 예상된다. 그리고 차양장치가 없는 경우 일반적인 온도구배를 나타내고 있었다. 한편 남동향과 남서향에 외부 차양장치가 설치되었을 때 남서향의 외측 유리 표면온도가 더 낮게 나타나는 특징이 있다. 이 결과는 천공복사에 의한 냉방 저감 효과를 정량화할 수는 없지만 적어도 타당성은 확인할 수 있었다. 향후 연구에서는 천공복사 냉각과 에너지 소비 사이의 상관관계를 조사하고 외부 차양장치의 난방에너지 절감 효과에 대한 독립 챔버 실험을 진행할 계획이다.

• 한국태양에너지학회:학술대회논문집
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• 한국태양에너지학회 2009년도 추계학술발표대회 논문집
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• pp.32-37
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• 2009

An energy loss through the window system occupies about 10 to 30 percent on energy consumption of the whole building. That is the reason, several elements for a building composition of window system are the weakest from the heat. Insulation performance increases for the reducing heat loss. Heat transfer through the window system that is reducing heat transfer through conduction, convection and radiation. Insulation performance reinforcement methods classify improving heat specific quality of window system and improving efficiency of whole window system. The most application method among each methods is reducing emission ratio of the window system(Low-E glass), increasing a number of glazing(multiple window) and a method of vacuuming between glazing and glazing. Therefore this study is investigated a sort of glazing and specific character, U-value calculation with changing glazing thickness and calculation of temperature distribution and U-value with a glazing charging gas kind from double glazing. For a conclusion, an aspect of U-value figure at the smallest value case of vacuum glazing with Low-E coating. That means insulation efficiency is the best advantage during a building plan selecting vacuum glazing with Low-E coating for a energy saving aspect. In this way, U-value become different the number of glazing, coating whether or not and selecting injection gas. Therefore selecting of glazing is very important after due consideration by a characteristic and use of building and consideration of strong point and weak point.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2006년도 추계학술대회논문집
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• pp.17-20
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• 2006

Korean traditional houses have been developed in sympathy with natural environment and formed comfortable indoor condition by properly using surrounding natural resources including building layout, space construction and material our traditional wooden windows adjusting ambient temperature and humidity have both the functions of window and door, although they are clearly divided in the West. While window paper is attached from the outside in China and Japan, it is attached from the inside in Korea. The opening and closing mode of windows is similar and their dimensions are shown not to he standardized but diverse in terms of the characteristic of wooden furniture and that of components placed between columns. Thus this study is to look into the performance of band-lattice door of a typical traditional one by observing changes in sound absorption characteristics according to difference in thickness and finishing method of window paper and those in sound absorption characteristics with the changed thickness of air layer in traditional windows and doors.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2002년도 학술대회지
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• pp.39-42
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• 2002

The nuclear transmutation technology to Incinerate the long lived radioactive nuclides and produce energy during the incineration process is believed to be one or the best solutions. HYPER(${\underline{HY}}brid {\underline{P}}ower {\underline{E}}xtraction {\underline{R}}$eactor)is the accelerator driven transmutation system which is being developed by KAERI(Korea Atomic Energy Research Institute). Lead-bismuth(Pb-Bi) is adopted as a coolant and spallation target material. In this paper, we performed the thermal-hydraulic analysis of HYPER target using the commercial code FLUENT, and also calculated thermal and mechanical stress of the beam window using the commercial code ANSYS. It is found that there is an optimum value for the window diameter and the maximum allowable beam current can be increased to 17.3 mA for the inner diameter of windows, 40 cm. Finally, the other shapes such as uniform or scanned beam were considered. The results of FLUENT calculations show that the uniform type is preferable to the other shapes of the beam in terms of the window and target cooling and the maximum window temperature is lower than that of the parabolic beam by $58 ^{\circ}C$ for the beam current, 13 mA.

• 설비공학논문집
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• 제24권4호
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• pp.351-357
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• 2012

To reduce the summertime cooling load of a plant factory, a concept design was performed for the double skin window which utilizes the low temperature air from a ground coupled heat exchanger. The design parameters were selected as the number of cavity air inlet, the cavity thickness, the location of cavity air inlet, and the configuration of cavity air outlet. A parametric study was conducted in a systematic way to evaluate the heat transfer characteristics of the double skin window. As the number of cavity air inlet and the cavity thickness increase, the heat flux from outside air to indoor air was decreased. The effect of the location of cavity air inlet was not significant and the larger cavity air outlet area gave us relatively better heat blocking performance from outside hot air. This study demonstrated that it is possible to develop an improved double skin window by utilizing a ground coupled heat exchanger.

• 농업생명과학연구
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• 제45권6호
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• pp.265-278
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• 2011

하절기 온실 내 온도와 상대습도를 동시에 제어할 목적으로 압축공기를 이용한 이류체 분무 포그 냉방을 도입한 유리온실에서 측창의 개폐수준이 온실내의 온도와 상대습도 제어에 어떠한 영향을 주는지 분석하였다. 제어과정은 온실 환경변수들을 측정하고, 이를 반영하여 온실 내 수분평형방정식과 열평형방정식을 정립한 다음, 이 방정식들을 프로그램으로 코딩하여 각 사이클의 천창 개폐량과 포그 분무량을 결정하고 제어하였다. 온실의 온습도 제어목표는 온도와 습도를 각각 28, 75%로 설정하였고, 실험은 측창이 전혀 열리지 않은 0%, 50% 열린 경우, 100% 열린 경우 세 가지 모드를 비교분석하였다. 제어실험결과 온실 내 건구온도의 평균은 모드에 따라 각각 28.2, 27.2 $26.3^{\circ}C$로 나타났으며, 표준편차는 $0.4{\sim}0.8^{\circ}C$이었다. 상대습도는 측창을 완전히 닫은 모드인 0%의 경우 평균 76.3% 정도로서 목표 상대습도인 75%에 상당히 근접해서 제어되고 있었으며, 표준편차가 2.1%로서 다른 모드에 비해 상당히 안정된 범위에서 유지되는 것으로 나타났다. 0%의 모드에서 가장 목표온도로 잘 제어되고 있는 것으로 나타났다.

• 대한원격탐사학회지
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• 제24권1호
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• pp.65-78
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• 2008

This study compares the relative accuracy and consistency of four split-window land surface temperature (LST) algorithms (Becker and Li, Kerr et ai., Price, Ulivieri et al.) using 24 sets of Terra (Aqua)/Moderate Resolution Imaging Spectroradiometer (MODIS) data, observed ground grass temperature and air temperature over South Korea. The effective spectral emissivities of two thermal infrared bands have been retrieved by vegetation coverage method using the normalized difference vegetation index. The intercomparison results among the four LST algorithms show that the three algorithms (Becker-Li, Price, and Ulivieri et al.) show very similar performances. The LST estimated by the Becker and Li's algorithm is the highest, whereas that by the Kerr et al.'s algorithm is the lowest without regard to the geographic locations and seasons. The performance of four LST algorithms is significantly better during cold season (night) than warm season (day). And the LST derived from Terra/MODIS is closer to the observed LST than that of Aqua/MODIS. In general, the performances of Becker-Li and Ulivieri et al algorithms are systematically better than the others without regard to the day/night, seasons, and satellites. And the root mean square error and bias of Ulivieri et al. algorithm are consistently less than that of Becker-Li for the four seasons.

• 설비공학논문집
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• 제29권9호
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• pp.455-462
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• 2017

The purpose of this study is to analyze heating and cooling load variation due to envelope retrofits in an old school building. In a previous study, envelope retrofit of an old school building resulted in annual energy consumption reduction. However, cooling energy consumption increased with the envelope retrofit. This is because of high internal heat generation rates in school buildings and internal heat cannot escape through windows or walls when the envelope's thermal performance improves. To clarify this assumption, thermal performance changes due to envelope retrofits were analyzed by simulation. Results revealed indoor temperature and inner window surface temperature increased with high insulation level of windows. Indoor heat loss through windows by conduction, convection and radiation decreased and resulted in an increase of cooling load in an old school building. From results of this study, energy saving impact of envelope retrofits in an old school building may not be significant because of high internal heat gain level in school buildings. In case of replacing windows in school buildings, local climate and internal heat gain level should be considered.

• 한국정밀공학회지
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• 제30권9호
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• pp.1001-1006
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• 2013

Projection-based stereolithography is divided into constrained-surface and free-surface type according to controlling liquid layer. The constrained-surface type has a uniform layer thickness due to the use of a projection window, which covers the pattern generator such as liquid crystal display. However, the adhered resin on the projection window causes trouble and requires great separation force when the cured layer is separated from the window. To minimize the separation force, we developed a system to measure the separation force. The influence of material covering the pattern generator and the resin temperature is investigated in the system. Several structures according to the resin temperature and the velocity of z-axis elevation are compared. As a result, the fabrication condition to minimize the separation force reduces the process time.

• 한국태양에너지학회:학술대회논문집
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• 한국태양에너지학회 2012년도 춘계학술발표대회 논문집
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• pp.171-176
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• 2012

This research on building Integrated Photovoltaic System replacing windows and doors with amorphous silicon thin film PV windows and doors installing same exact mount on Mock-up. The windows and doors should be installed in different angle and bearing so that we can analyse the amount of electricity from them. The objective of the research is to evaluate and investigate the relationship between factors(intensity of solar radiation, PV window surface temporature, incidence angle, and sky conditions) that affects performance of PV window and performance. The range and method of this research is to establish mornitoring system and analysis the date from the mornitoring system to evaluate the performance of PV windows that has thin film of solar battery. We should evaluate the insolation according to the position of PV window, output, and surface temperature according to months and seasons so that we can figure out the relationship between these. And we should investigate the relationship between performance and efficiency according to incidence angle and sky condition so that we can figure out the correlation between factors and performance.